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arXiv · 1505.05614

Tuneable on-demand single-photon source

Z. H. Peng·J. S. Tsai·O. V. Astafiev
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Abstract

An on-demand single photon source is a key element in a series of prospective quantum technologies and applications. We demonstrate the operation of a tuneable on-demand microwave photon source based on a fully controllable superconducting artificial atom strongly coupled to an open-end transmission line (a 1D half-space). The atom emits a photon upon excitation by a short microwave $π$-pulse applied through a control line weakly coupled to the atom. The emission and control lines are well decoupled from each other, preventing the direct leakage of radiation from the $π$-pulses used for excitation. The estimated efficiency of the source is higher than 75\% and remains to be about 50\% or higher over a wide frequency range from 6.7 to 9.1 GHz continuously tuned by an external magnetic field.

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Z. H. Peng, J. S. Tsai, O. V. Astafiev. 2015-05-21. Tuneable on-demand single-photon source. https://doi.org/10.1038/ncomms12588

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